950 resultados para Zero reference level


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Analysing census and industry data at the metro and neighbourhood levels, this paper seeks to identify the location characteristics associated with artistic clusters and determine how these characteristics vary across different places. We find that the arts cannot be taken overall as an urban panacea, but rather that their impact is place-specific and policy ought to reflect these nuances. However, our work also finds that, paradoxically, the arts’ role in developing metro economies is as highly underestimated as it is overgeneralised. While arts clusters exhibit unique industry, scale and place-specific attributes, we also find evidence that they cluster in ‘innovation districts’, suggesting they can play a larger role in economic development. To this end, our results raise important questions and point toward new approaches for arts-based urban development policy that look beyond a focus on the arts as amenities to consider the localised dynamics between the arts and other industries.

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Safety at railway level crossings (RLX) is one part of a wider picture of safety within the whole transport system. Governments, the rail industry and road organisations have used a variety of countermeasures for many years to improve RLX safety. New types of interventions are required in order to reduce the number of crashes and associated social costs at railway crossings. This paper presents the results of a large research program which aimed to assess the effectiveness of emerging Intelligent Transport Systems (ITS) interventions, both on-road and in-vehicle based, to improve the safety of car drivers at RLXs in Australia. The three most promising technologies selected from the literature review and focus groups were tested in an advanced driving simulator to provide a detailed assessment of their effects on driver behaviour. The three interventions were: (i) in-vehicle visual warning using a GPS/smartphone navigation-like system, (ii) in-vehicle audio warning and; (iii) on-road intervention known as valet system (warning lights on the road surface activated as a train approaches). The effects of these technologies on 57 participants were assessed in a systematic approach focusing on the safety of the intervention, effects on the road traffic around the crossings and driver’s acceptance of the technology. Given that the ITS interventions were likely to provide a benefit by improving the driver’s awareness of the crossing status in low visibility conditions, such conditions were investigated through curves in the track before arriving at the crossing. ITS interventions were also expected to improve driver behaviour at crossings with high traffic (blocking back issue), which were also investigated at active crossings. The key findings are: (i) interventions at passive crossings are likely to provide safety benefits; (ii) the benefits of ITS interventions on driver behaviour at active crossings are limited; (iii) the trialled ITS interventions did not show any issues in terms of driver distraction, driver acceptance or traffic delays; (iv) these interventions are easy to use, do not increase driver workload substantially; (v) participants’ intention to use the technology is high and; (vi) participants saw most value in succinct messages about approaching trains as opposed to knowing the RLX locations or the imminence of a collision with a train.

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The increasing interest in nanoscience and nanotechnology has prompted intense investigations into appropriate fabrication techniques. Self-organized, bottom-up growth of nanomaterials using plasma nanofabrication techniques1–10 has proven to be one of the most promising approaches for the construction of precisely tailored nanostructures (i.e., quantum dots,11–13 nanotubes,14–17 nanowires,18–20 etc.) arrays. Thus the primary aim of this chapter is to show how plasmas may be used to achieve a high level of control during the self-organized growth of a range of nanomaterials, from zero-dimensional quantum dots (Section 15.2) to one- and two-dimensional nanomaterials (Section 15.3) to nanostructured films (Section 15.4)...

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Mutation of the BRAF gene is common in thyroid cancer. Follicular variant of papillary thyroid carcinoma is a variant of papillary thyroid carcinoma that has created continuous diagnostic controversies among pathologists. The aims of this study are to (1) investigate whether follicular variant of papillary thyroid carcinoma has a different pattern of BRAF mutation than conventional papillary thyroid carcinoma in a large cohort of patients with typical features of follicular variant of papillary thyroid carcinoma and (2) to study the relationship of clinicopathological features of papillary thyroid carcinomas with BRAF mutation. Tissue blocks from 76 patients with diagnostic features of papillary thyroid carcinomas (40 with conventional type and 36 with follicular variant) were included in the study. From these, DNA was extracted and BRAF V600E mutations were detected by polymerase chain reaction followed by restriction enzyme digestion and sequencing of exon 15. Analysis of the data indicated that BRAF V600E mutation is significantly more common in conventional papillary thyroid carcinoma (58% versus 31%, P = .022). Furthermore, the mutation was often noted in female patients (P = .017), in high-stage cancers (P = .034), and in tumors with mild lymphocytic thyroiditis (P = .006). We concluded that follicular variant of papillary thyroid carcinoma differs from conventional papillary thyroid carcinoma in the rate of BRAF mutation. The results of this study add further information indicating that mutations in BRAF play a role in thyroid cancer development and progression.

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We no longer have the luxury of time as the effects of climate change are being felt, according to the latest Intergovernmental Panel on Climate Change report, on every continent and in every ocean. More than 50% of the population of the United States and 85% of Australians live in coastal regions. The number of people living in the world’s coastal regions is expected to increase along with the need to improve capacity to mitigate hazards , and manage the multiple risks that have been identified by the scientific community. Under the auspices of the Association of Collegiate Schools of Architecture (ACSA) design academics and practitioners from the Americas, Asia, and Australia met in Fort Lauderdale, Florida for the fourth Subtropical Cities international conference to share outcomes of research and new pedagogies to address the critical transformation of the physical environments and infrastructures of the world’s vulnerable coastal communities. The theme of Subtropical Cities, adopted by the ACSA for its Fall 2014 Conference, is not confined entirely to a latitudinal or climatic frame of reference. The paper and project presentations addressed a range of theoretical, practice-led, and education-oriented research topics in architecture and urban design related to the subtropics, with emphasis on urban and coastal regions. More than half the papers originate from universities and practices in coastal regions. Threads emerged from a tapestry of localized investigations to reveal a more global understanding about possible futures we are designing for current and future generations. The one hundred-plus conference delegates and presenters represented 33 universities and institutions from across the United States, Mexico, Canada, Australia, the Middle East, Peru and China. Case studies from India, Morocco, Tahiti, Indonesia, Jordan, and Cambodia were also presented, expanding the global knowledge base. Co-authored submissions presented new directions for architecture and design, with a resounding theme of collaboration across diverse disciplines. The ability to deal with abstraction and complexity, and the capacity to develop synthesis and frameworks for defining problem boundaries can be considered key attributes of architectural thinking. Such a unique set of abilities can forge collaboration with different professional disciplines to achieve extraordinary outcomes. As the broad range of papers presented at this conference suggest, existing architectural and urban typologies and practices are increasingly considered part of the cause and not the solution to adapting to climate change and sea level rise. Design responses and the actions needed to generate new and unfamiliar forms of urbanism and infrastructure for defense, adaptation, and retreat in subtropical urban regions are being actively explored in academic design studios and research projects around the world. Many presentations propose provocative and experimental strategies as global climate moves beyond our “comfort zone”. The ideas presented at the Subtropical Cities conference are timely as options for low-energy passive climatic design are becoming increasingly limited in the context of changing climate. At the same time, ways of reducing or obsoleting energy intensive mechanical systems in densely populated urban centres present additional challenges for designers and communities as a whole. The conference was marked by a common theme of trans-disciplinary research, where design integration with emerging technologies resonate with a reaffirmation of the centrality of design thinking, expanding the scope of the traditional architecture studio pedagogy to integrate knowledge from other disciplines and the participation of diverse communities.

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This thesis has developed a new approach to trace virtual protection signals in Electrical substation networks. The main goal of the research was to analyse the contents of the virtual signals transferred, using third party software. In doing so, a comprehensive test was done on a distance protection relay, using non-conventional test equipment.

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Purpose – Simple linear accounts of prescribing do not adequately address reasons “why” doctors prescribe psychotropic medication to people with intellectual disability (ID). Greater understanding of the complex array of factors that influence decisions to prescribe is needed. Design/methodology/approach – After consideration of a number of conceptual frameworks that have potential to better understand prescribing of psychotropic medication to adults with ID, an ecological model of prescribing was developed. A case study is used to outline how the model can provide greater understanding of prescribing processes. Findings – The model presented aims to consider the complexity and multi-dimensional nature of community-based psychotropic prescribing to adults with ID. The utility of the model is illustrated through a consideration of the case study. Research limitations/implications – The model presented is conceptual and is as yet untested. Practical implications – The model presented aims to capture the complexity and multi-dimensional nature of community-based psychotropic prescribing to adults with ID. The model may provide utility for clinicians and researchers as they seek clarification of prescribing decisions. Originality/value – The paper adds valuable insight into factors influencing psychotropic prescribing to adults with ID. The ecological model of prescribing extends traditional analysis that focuses on patient characteristics and introduces multi-level perspectives that may provide utility for clinicians and researchers.

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Organizations are increasingly seeking stakeholder support through engagement to demonstrate their corporate social responsibility (CSR) credentials. These credentials are in turn used to support claims of legitimacy for organizational operations. This paper uses a process model of antecedents, implementation, and consequences to study the connection between engagement and CSR. CSR reports show organizations perceive engagement in CSR as both communication and activities between organizations and their stakeholders; and as a second, meta-level of communication about that engagement with stakeholders beyond those directly involved, thereby broadening the scope of organizational claims to legitimacy. Understanding what engagement is and how and why it is carried out in CSR provides a framework for understanding engagement in public relations.

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Supercapacitors are increasingly used as short term energy storage elements in distributed generation systems. The traditional approach in integrating them to the main system is the use of interfacing dc-dc converters which introduce additional costs and power losses. This paper therefore, presents a novel direct integration scheme for supercapacitors and thereby eliminates associated costs and power losses of interfacing converters. The idea is simply to replace ordinary capacitors of three-level flying-capacitor rectifiers with supercapacitors and operate them under variable voltage conditions. An analysis on the reduction of power losses by the proposed system is presented. Furthermore, supercapacitor sizing and implementation issues such as effects of the variable voltage operation and resistive behavior of supercapacitors at high frequencies are also discussed. Simulation results are presented to verify the efficacy of the proposed system in suppressing short term power fluctuations in wind generation system.

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Work–life interference is important for school-aged workers because it influences their educational outcomes/career aspirations. Although research highlights the role of work hours in determining work–life interference for these workers, work/job-level characteristics have received limited attention. Using survey data from Queensland school students who work part-time, we assess the influence of a range of employment-level variables on work–life interference. The results of multiple regression analysis indicate work–life interference is exacerbated by having low trust in managers and limited scope to refuse work hours and stability in work hours, emphasising the importance of organisational variables in integrating work and non-work spheres for school-aged workers.

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The social media statistics of South Africa reveal an exponential increase in the use of social media. Libraries, as part of a community, cannot ignore this! Social media provide libraries instant and direct connection with their members regardless their geographical location. This paper explores social media use in libraries. The establishment of social media for the SABC Media Libraries is discussed to demonstrate a practical implementation of social media in libraries and archives. Tips and resources, with specific mention to Twitter and Facebook, as well as social media etiquette and social media policy guidelines are supplied. The literature of published articles and Infographic show the changing role of librarians in the social media era and the need for librarians to keep learning and update their skills to accommodate users’ needs. The focus should now be on how well we do social media for the library, not on whether we should do it or not!

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This paper presents a novel battery direct integration scheme for renewable energy systems. The idea is to replace ordinary capacitors of a three-level flying-capacitor inverter by three battery banks to alleviate power fluctuations in renewable generation. This approach eliminates the need for interfacing dc-dc converters and thus considerably improves the overall efficiency. However, the major problem with this approach is the uneven distribution of space vectors which is due to unavoidable unbalance in clamping voltages. A detailed analysis on the effects of this issue and a novel carrier based pulse width modulation method, which can generate undistorted currents even in the presence of unevenly distributed space vectors, are presented in this paper. A charge/discharge controller is also proposed for power sharing and state of charge balancing of battery banks. Simulation results are presented to verify the efficacy of the proposed system, modulation method and power sharing controller.

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This paper presents a new direct integration scheme for supercapacitors that are used to mitigate short term power fluctuations in wind power systems. The idea is to replace ordinary capacitors of a 3-level flying capacitor inverter by supercapacitors and operate them under variable voltage conditions. This approach eliminates the need of interfacing dc-dc converters for supercapacitor integration and thus considerably improves the overall efficiency. However, the major problem of this unique system is the change of supercapacitor voltages. An analysis on the effects of these voltage variations are presented. A space vector modulation method, built from the scratch, is proposed to generate undistorted current even in the presence of dynamic changes in supercapacitor voltages. A supercapacitor voltage equalisation algorithm is also proposed. Furthermore, resistive behavior of supercapacitors at high frequencies and the need for a low pass filter are highlighted. Simulation results are presented to verify the efficacy of the proposed system in suppressing short term wind power fluctuations.

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This study reports the synthesis, characterization and application of nano zero-valent iron (nZVI). The nZVI was produced by a reduction method and compared with commercial available ZVI powder for Pb2+ removal from aqueous phase. Comparing with commercial ZVI, the laboratory made nZVI powder has a much higher specific surface area. XRD patterns have revealed zero valent iron phases in two ZVI materials. Different morphologies have been observed using SEM and TEM techniques. EDX spectrums revealed even distribution of Pb on surface after reaction. The XPS analysis has confirmed that immobilized lead was present in its zero-valent and bivalent forms. ‘Core-shell’ structure of prepared ZVI was revealed based on combination of XRD and XPS characterizations. In addition, comparing with Fluka ZVI, this lab made nZVI has much higher reactivity towards Pb2+ and within just 15 mins 99.9% removal can be reached. This synthesized nano ZVI material has shown great potential for heavy metal immobilization from waste water.

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Nano Zero valent iron (Fe0) were reported as an effective material for azo dye removal, however, similar to other nano-materials, ultra-fine powder has a strong tendency to agglomerate into larger particles, resulting in an adverse effect on both effective surface area and catalyst performance. Here we report nano sized Fe0 particles dispersed onto the surface of natural bentonites. X-ray diffraction was used to study the sample phases. Scanning electron microscopy and transmission electron microscopy were applied to study the morphology and morphological changes. Spherical individual Fe0 particles were observed after dispersion onto bentonites, and these samples were used for orange II (OII) decolourization with wide working pH range. Higher reactivity is attributed to good dispersion of Fe0 particles on clay minerals’ surface. This study is significant for providing novel modified clay based catalyst materials for the decolourization of azo dye contaminants from wastewater.